IES-VE User Forum

Dear All,

Basically i have run cibse loads for a hotel project from APCHE module and end up lets say 500KW(After suncast)
After the load results I have run the Dynamic simulation (part-L) complaince and again run the loads from the same point like Vista results. My query is does the CIBSE load results at APCHE module would be the same Load results after Dynamic simulation as well? Hope some one would respond to me.

Cheers

Further to my earlier query...

Does the cibse loads purely based on room template values like heating/cooling temparatures, gains & infiltration. OR ELSE the CIBSE loads would also depend on the corresponding NCM system too?

Hi,

I'm not quite sure if I understand you correctly here but the Apache system you use (as well as the room thermal templates) will affect the CIBSE loads results.

Some quick tests should be able to answer your query here? for example do 2 runs with the same system but improve efficiency in the second run and compare the chiller/boiler loads and you will see the change.

As CIBSE loads calculation and Apache Simulation are different calculations I would expect you will see different results between these. Some further information can be found int he calculation methods documents which you can view from <VE> Help >> User Guides then check the Thermal >> Reference section.

Phil

Hey just on the CIBSE loads method that formula used is the one form Guide A Φt = [F1cu Σ (A U) + F2cu Cv] (θc– θao)

but here is my question when i run the loads and then do a manual one to compare there is a difference of around 5-15 % difference in the results i am curious what would be the factors that ies take differently to CIBSE and how there is a difference if they are the same formula ?

and if there is what are the factors that would cause this ?

I hope this link is the best answer for you

http://www.ibpsa.org/proceedings/BS1999/BS99_PB-16.pdf